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According to kinetic theory of gases,
A. The motion of the gas molecules freezes at 0°C
B. The mean free path of gas molecules decreases if the density of molecules is increased.
C. The mean free path of gas molecules increases if temperature is increased keeping pressure constant.
D. Average kinetic energy per molecule per degree of freedom is 3/2 kB T (for monoatomic gases).
Choose the most appropriate answer from the options given below:
- A and C only
- B and C only
- A and B only
- C and D only
Correct answer: B and C only
Solution
Option B is correct because increasing the density of gas molecules leads to more frequent collisions, thus reducing the mean free path. Option C is also correct as increasing the temperature at constant pressure results in higher kinetic energy and greater mean free path due to increased molecular speed.
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